Audio playback systems, such as stereo receivers, Audio/Video (AV) receivers, portable stereos, amplified speaker systems, and the like, may receive an audio stream from any one of a number of audio sources and render the audio stream as sound over speakers. The audio stream may be an uncompressed digital audio stream, such as a Linear Pulse-Code Modulation (LPCM) encoded stream, or a compressed digital audio stream that has been created using either a lossless compression technology, such as the Free Lossless Audio Codec (FLAC), or a lossy compression technology, such as MPEG-1 or MPEG-2 Audio Layer III (MP3).
Rendering of audio at the audio playback system may entail processing the audio stream in various ways, e.g., to improve, enhance, or customize the sound that is generated by the audio playback system. This rendering may entail the use of a Digital Signal Processor (DSP), which may be an Application Specific Integrated Circuit (ASIC, i.e. a chip) that is hardwired within the audio playback system. For example, a DSP chip may provide alternative audio field simulations for generating different audio effects such as “hall,” “arena,” “opera” and the like, which simulate, e.g. using surround sound and echo effects, audio playback in different types of venues.
The nature of the audio rendering that is performed by the audio playback system may be predetermined and fixed, or may be user-selectable from only a finite number of predetermined alternatives. This may be due to limited or fixed audio processing capabilities of the ASIC DSP, or other components, that may be used at the audio playback system for rendering audio. Sound quality may vary depending upon the audio rendering that is performed, the physical attributes of the speakers over which the sound is played (e.g. size, number, configuration, wattage, etc.), and/or the physical characteristics of a room in which the sound is played (e.g. anechoic quality or amount of reverberation).